Characterization and reactivity of WO3–V2O5 supported on sulfated titanium pillared clay catalysts for the SCR-NO reaction

Abstract

Vanadia and tungsten oxides supported on sulfated Titanium pillared clay were prepared and characterized by N-2 physisorption, XRD, XPS, NH3-TPD and H-2-TPR measurements. The effect of vanadium and tungsten oxides on the catalytic activity of sulfated Ti-pillared clay (STi-PILC) for NO reduction by ammonia was examined. Based on the temperature-programmed reduction, it was found that the sulfate stability depends on the loaded metal oxides and the reduction properties of SO42- or V2O5 in the sample were changed in the presence of WO3. The difference in reduction properties of sulfate strongly suggests some interaction of sulfate with tungsten and vanadia species on the surface of STi-PILC support. Vanadia enhanced the NO removal activity of STi-PILC, while no significant effect of tungsten was observed for WO3-V2O5/STi-PILC catalyst. When both tungsten and sulfate exist simultaneously on the surface of vanadia supported STi-PILC, the sulfate species seems to play a more important role for NO removal activity than tungsten. To cite this article: L. Khalfallah Boudali et al., C R. Chimie 12 (2009). (C) 2008 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.